feat: add tags workflow

src/projectConfig/parseProjectConfig.ts

@@ -0,0 +1,73 @@
+import * as yaml from "js-yaml";
+import { err, ok, Result } from "neverthrow";
+import { appError, AppError, AppErrorVariant } from "@/error";
+import {
+	EMPTY_PROJECT_CONFIG,
+	normalizeTag,
+	type ProjectConfig,
+} from "@/model/projectConfig";
+
+/**
+ * Parse task-folder config.yml content.
+ * Accepts missing/empty tags → [].
+ */
+export function parseProjectConfig(
+	content: string,
+): Result<ProjectConfig, AppError> {
+	if (content.trim() === "") {
+		return ok({ ...EMPTY_PROJECT_CONFIG });
+	}
+
+	let data: unknown;
+	try {
+		data = yaml.load(content);
+	} catch (error) {
+		const detail = error instanceof Error ? error.message : "invalid YAML";
+		return err(
+			appError(AppErrorVariant.INVALID_PROJECT_CONFIG, { detail }),
+		);
+	}
+
+	if (data === null || data === undefined) {
+		return ok({ ...EMPTY_PROJECT_CONFIG });
+	}
+
+	if (typeof data !== "object" || Array.isArray(data)) {
+		return err(
+			appError(AppErrorVariant.INVALID_PROJECT_CONFIG, {
+				detail: "root must be a mapping",
+			}),
+		);
+	}
+
+	const record = data as Record<string, unknown>;
+	if (record.tags === undefined) {
+		return ok({ tags: [] });
+	}
+
+	if (!Array.isArray(record.tags)) {
+		return err(
+			appError(AppErrorVariant.INVALID_PROJECT_CONFIG, {
+				detail: "tags must be an array of strings",
+			}),
+		);
+	}
+
+	const tags: string[] = [];
+	const seen = new Set<string>();
+	for (const item of record.tags) {
+		if (typeof item !== "string") {
+			return err(
+				appError(AppErrorVariant.INVALID_PROJECT_CONFIG, {
+					detail: "tags must be an array of strings",
+				}),
+			);
+		}
+		const tag = normalizeTag(item);
+		if (!tag || seen.has(tag)) continue;
+		seen.add(tag);
+		tags.push(tag);
+	}
+
+	return ok({ tags });
+}